\begin{tikzpicture}[scale=0.9]
    \tkzDefPoints{0/0/B,  3/0/C,  0.8/2/A, 3.8/2/D}

    \tkzDrawPolygon(A,B,C,D)
    \tkzLabelPoints[left](B)
    \tkzLabelPoints[right](C)
    \tkzLabelPoints[above](A,D)
\end{tikzpicture}

